Digital data communication environments often involve the placement of communications media in close proximity to one another. As communication systems increase the data rates at which they attempt to communicate, it is often the case that the bandwidth of the signals is increased to accommodate the increased data rate. The increased bandwidth of the communication signals increases the problems associated with electromagnetic cross-talk between communication media placed close to one another. Under certain circumstances an induced signal can be created on a unconnected communication media which will cause a communication system connected to the head-end of the communication media to believe that a transmission is being attempted on the communication link. This condition is referred to as a phantom signal or phantom link. The presence of phantom links can greatly disrupt the overall performance of a digital data communication system and distract resources within the system from the processing of data through actual links.
Digital communication systems often utilize the transmission of data in packets. Typically, each packet may contain a preamble which enables synchronization with the far-end recipient. In conventional systems, the preamble used to identify data packets are predetermined numbers which are stored by the head-end data switch. Typically in conventional systems, the same preamble numbers may be used to identify data packets on parallel communication channels and are therefore not unique to any particular communication session.